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Old 07-27-2014, 07:18 AM
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GregWeld GregWeld is offline
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Originally Posted by speED View Post
BBC 460 cu. in., 950 Holley HP, edelbrock victor jr, edelbrock 355 cnc heads, 10.65:1, .600/ .630 lift solid roller, 245 duration @ .050. Heads are new and raised my compression from 10.25 to 10.65.

Ron,
When I retarded the timing my idle rpm didn't change much so I never raised the idle speed and therefor uncovered the transfer slot. I agree and was originally taught for racing purposes more timing at idle is better but don't you agree for the street you will need a curve in order to prevent detonation during normal driving on the street.


That compression value is only a "static" compression calculation. What's more important - and can actually be measured - is your CYLINDER PRESSURE. The cam bleeds off "compression" so regardless of what static compression the pistons rating is - and the size of the head gasket - and the size of the chamber in the head... the cam will play a significant roll in the cylinder pressures being generated. With the cam you have and that static compression ratio -- my guess is you're making less cylinder pressure in that BBC than one might think. Aluminum heads are a giant heat sink.

The Edelbrock E-CNC head comes in two chamber sizes -- 110 and 118cc - which one are you running?

With improved combustion chamber - and your distributor set up as stated, would have had a very retarded timing curve and a total of 37* --- it's little wonder you're having "issues".
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